Aerial spray mechanism



June 8, 1954 Filed Feb. 9, 1950 2 Sheets-Sheet l t V INVENTO/i f Robert Allen 1 /766 /2 5) ATTOR/VIYS Patented June 8, 1954 ATENT ICE AERIALWSPRAY MECHANISM I 1RobertAllen Price, Williamsville,.N. Y.,,.as signor toBellAircraftCorporation; Buffalo; NI Y.

-1.Application February 9,1950,. SeriaLNo.:-143,277

trol,.- fertilizing,- and :like operations, .have been:

recognized for some-years. Morerecentlyxrotary wing. aircraft. .such: as the. helicopter, .have been found especially-suited: to :this. work. because of their slow :xforward-speed and". characteristic downrush of air-underthe rotor. 'In. spraying foliage, this downrush'ofair has been found especiallyadvantageous when used in conjunction-with a fine fog -type spray-because the downdraft" of air in such cases carries the fog to the ground-,and then eddies up under the leaves,"thereby coatingthe-undersides of the leaves with spray material. Ontheother hand, a coarser spray is more elficient for treating open areas, suchasswamplands for exampley and in asmuch as modern-methods often contemplate single fiights'over' varying" terrain it is highly desirable toprovide means whereby the pilot may adjust the coarseness of? the spray while in flight.

The primary object. ofthis invention is to provide an improved aerialspray system which will enable the operatorthereof while. in flight to changeat will-the.type of spray-generated, so as to suit-the'varying requirements of the terrain traversed.

Another; object: of :the: invention is to provide a system .for. controllingrthe. coarseness. of such aspray as set forth hereinabve;;.whichiwil1 utilize standard 1 commercially. available: components,

and which will be simple anclifreliabl-e; in operation.

Other? objects :and advantages." of: theinvention will;appear inthe specification hereinafter. III the drawing: I Fig.1 is adiagrammatic fragmentary perspective viewrof a ;helicopterzwith a..-spraycontrol according to the invention;

'notshown theexhaust manifolds thereof are indicated. at.- Iii-I6 and-are arranged to, supply hot gases. to a pair. ofrspray heads l8- I8, which may .beof anyssuitable; type-.suchms ':the:TOdd Shipyards .No; 317 17:11 Qe :,-generator. head that: will generate different :sized spray droplets accord- 1 ing to the rate atewhichythey-are supplied with spray, material.

The insecticidegor otherzfluid to =.-be sprayed is supplied froma pair of tanks-or hoppers 20-20 to the spray heads I8.l8;by.means of-conduits 22-23 and a pumpz24; together with a dual control system of thepresentdnvention. .This novel control systemcomprises. a; pair of normally closed solenoid valves. 2 6;-.28 two pair of needle valves 32.-32 and 34-;34 and suitable conduits 30 and 35. As is most clearlyishown in'Fig. 2,

. the solenoid valves-26+Z87are1fed in parallel from the pump 24 through-the conduit 30. Each soleof needle valves: 32%32 and Alida-.34.

noid valve Err-28in turn feeds a separate pair Thus, the solenoid valve-26 controlsthe-supply to the'needle valves 32-32 and ,-the solenoid valve 28 controls the supply. to the needle valves 1341-34. Finally, correspondingneedle-valves of each said .pair are connected in parallel to feed one spray -head- I8;

I the other needle. valvesofthe-saidpairs being connected in parallel to the other-spray head l8.

Any .suitable controlrmeansnmay :be employed for the operation of theepumpltl. and the solenoid valvesv 26-28 while-theaircraft isin flight, such as for example, the electrical circuit shown in Fig. 3. In.,the illustratedcontrol, one side of a doublevpole Singlethrowpowerswitchbfl is connected to adirect-cur-rent:powersource 52 by means of conductors --54- .-..56. and a circuit ductors l889.

.7 5 is connected to. ground.

breaker58. Oneterminal of, the other'side of theswitch 50, isconnectedto-terminalfiZ of a triple pole normally open relay $6. bymeans of a conductor-64. Terminal 60 is also-connected to terminalv 68. of a normally closed-single pole relay l0- bymeans 'of.,.conduct;ors 64ll. .The coil 12 of the relay NJ is. connected between terminal 68 thereof and terminal 14 of asingle throw single polestop. switch 16., by means of the con- The;.other.side of the switch The otherterminal 82 of .the relay in is con nected by means; of a conduc tor.84- to one end of the coil 86 ofthe .rela-y.66 and the other end .of the coil' 86 isconnectecLto terminal88 of the -relay66andalso bymeans; of a conductor 90 and. connectable .theretobycontactor 91 thereof, is connected. to; grounds; A'j-umperr9flrjzconnects v-termina'l 62 of -the relay tozterminal599 there- I by means of contactor I02 of the relay 06 and connecting conductor I04. The other side of the pump motor I00 is connected to ground. A terminal I06 of the remaining contactor I08 of the relay 06 is connected by means of a conductor IIO to terminal II2 of a single pole double throw relay II4.

The relay II4 is spring biased so that its contactor II6 connects to terminal IIO when the coil I thereof is energized, and connects to terminal I22 when the coil I20 is not energized. Terminal I22 is connected to a normally closed solenoid valve 28 by means of a conductor I24, and terminal H8 is connected to a normally closed solenoid valve 26 by means of a conductor I26. The other sides of the solenoid valves 20-28 are connected to ground. A conductor I28, with a single pole single throw selector switch 30 interposed therein connects terminal I32 of the power switch 50 withone end of the coil I20 of the relay II4, the other end of the coil I20 being grounded. The power switch 50 labeled On- Off, and the selector switch I30 labeled Fog- Spray are conveniently on the instrument panel (not shown) of the aircraft, while the stop and start switches I0-94 may be embodied as buttons on the pilot control stick 38 (Fig. 1).

For example, in operation the needle valves 32-32 may be preset to meter fluid flow from the pump 24 to the spray heads I8-I8 at such a rate that the spray heads will produce a fine fog when the engine of the aircraft is running; while the other needle valves 343l may be preset to meter fluid flow from the pump 24 to the spray heads for the production of a heavier spray. Then, when the aircraft is in flight the pilot may cause the spray heads to emit either fine fog or heavier spray at will, according to which pair of needle valves he selects by energizing the corresponding solenoid valve. Thus, when the pilot wishes to spray an area, he will close the power switch 50 to on position, and turn the selector switch I30 to its open or spray position. Then he will close the start switch 94 momentarily, thus closing a circuit from the power source 52 through the power switch 50, the conductors 64'II, the relay I0, the conductor 04, the coil 86, and the conductor 90 to ground. This will energize coil 86 and thus the close relay 66.

As soon as the relay BE closes, contactor 91 thereof will connect the low end of the coil 86 directly to ground, by-passing the start switch 04 which may then be released without causing the relay 66 to reopen. When the relay 06 is closed, contactor I02 thereof will connect the pump motor I00 to the power supply through the conductor I04, jumper 98, conductor 64, and the power switch 50 while contactor I08 will supply power to open the solenoid valve 28 through the conductor IIO, contactor H6 of the relay H4, and the conductor I24. Thus, spray material will be pumped from the tanks 20 by the pump 24 operated by the pump motor I00 through the open solenoid valve 28 to the needle valves 34-34, which have been preset for spray operation before the flight. When the pilot desires to stop spraying, he will close the stop switch 70 momentarily, thus energizing the coil 12 of the relay I0. The relay I0 will then open, thereby deenergizing the coil 86 and thus opening the relay 05. The pump motor I00 will thus be stopped, and the solenoid valve 28 will reclose.

It will be understood that once the relay 66 opens, the connection from the coil 86 thereof to ground through contactor 9'! will be broken,

4 so that the coil 86 cannot be energized again until a new ground is established through the start switch 94.

To change from spray to fog operation, the pilot will simply throw the selector switch I30 to fog, or closed position. Then coil I20 will be energized and the relay II4 be actuated, thus switching the circuit of the conductor IIO from the conductor I24 to the conductor I20. Then when the start switch 94 is closed, closing the relay 60 as before, power will be supplied to the solenoid valve 20 instead of the solenoid valve 28. Thus, spray material will be pumped through the valve 26 to the needle valves 3232, which have been preset for fog operation. It will be obvious that the change from spray to fog may be made at will with or without first stopping the motor I00. It will also be obvious that whenever the power switch 50 is opened the motor and all coils in the system will be deenergized and the system will return to its normal inoperative condition regardless of whether it was running or not at the time.

Thus, the invention provides a spray control system with utmost flexibility and efficiency of operation, whereby the peculiar spray requirements of each area of ground may be satisfied in rapid succession as the spraying aircraft traverses varying terrain by the mere flip of a switch. Although only two sets of needle valves are used in the illustrated embodiment of the invention, it will be appreciated that any number of pairs could be used for as many choices of predetermined spray weights. Of course, an additional solenoid valve would be necessary for each additional pair of needle valves along with additional selection circuits.

I claim:

1. In an aerial spray system, a single source of spray fluid material, a single spray generating means of a type that will generate spray of different droplet sizes according to the rate at which spray material is delivered thereto, a system of schematically parallel conduits for delivering said spray material from said source to said spray generating means, preset spray fiuid metering means disposed to control flow through each of said conduits, valve means for separate control of said conduits, and pilot-operable control means for selective control of said valve means, whereby spray material may be delivered from said source to said spray generating means at difierent predetermined rates for generation of spray of the same spray material in different droplet sizes under the selective control of the pilot during flight.

2. In an aerial spray device, a source of spray material, a single spray generating means of a type that will generate sprays of different types according to the rate at which spray material is delivered thereto, means including functionally parallel conduit means for delivering said spray material from said source to said spray generating means, preset spray material metering means disposed and adapted to control flow through each of said conduit means at diiferent rates, valves for separate control of said conduit means, and pilot-operable remote control means for selective control of said valves including interlock means arranged so that only one of said valves is open at a given time, whereby spray material may be delivered from said source to said spray generating means at different predetermined rates for generation of spray of different types.

3. In an aerial spray system, a source of fluid spray material, a single spray generating means of a type that will generate spray of different; droplet sizes according to the rate at which spray material is delivered thereto, multiple preset control means for metering fluid flow from said source at different rates to said spray generating means, and pilot-operable control means for selective employment of said preset control means, whereby said spray generating means may be caused to emit spray of different predetermined coarsenesses upon manipulation of said pilot-operable control means.

4. In an aerial spray system, a pump. a single spray generating means of a type that will generate spray of diiferent droplet sizes according to the rate at which fluid is delivered thereto, dual preset control means for metering fluid flow from said pump to said spray generating means at different rates of flow, and pilot-operable control means for selective employment of said preset control means, whereby said spray generating means may be caused to emit relatively coarse spray or relatively fine fog upon adjustment of said pilot-operable control means.

5. In an aerial spray system, a single source 01' fluid spray material, a single spray generating means of a type that will generate spray of difierent droplet sizes according to the pressure at which spray material is delivered thereto, multiple preset control means for delivering fluid from said source at diiferent pressures to said spray generating means, and pilot-operable control means including interlock means for selective individual employment of said preset control means one to the exclusion of another, whereby said spray generating means may be caused to emit spray of the same spray material in different predetermined coarsenesses at the will of the pilot upon adjustment of said pilot-operable control means, according to which one of said preset control means is so employed.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,266,354 Christensen Dec. 16, 1941 2,335,716 Weeden Nov. 30, 1943 2,380,827 Downs July 31, 1945 2,511,626 Einbecker June 13, 1950 2,513,081 Clark June 27, 1950 2,564,392 Burrucker Aug. 14, 1951 

